Pharmaceutical composition containing sympathomimetic amine salt and co-distillable additive
A pharmaceutical composition is provided which contains a water soluble acid salt of a sympathomimetic amine, e.g., pseudoephedrine, and an additive, e.g., a volatile amine or other odorant, that is co-distillable, e.g., by steam distillation, with the sympathomimetic amine and/or its derivatives, e.g., its free base.
1. A pharmaceutical composition comprising a mixture which contains: i) a water soluble acid salt of a sympathomimetic amine, and ii) an additive that is co-distillable with the sympathomimetic amine as a free base, hydrochloride salt, or sulfate salt, wherein the additive is an odorant or a mixture of two or more odorants in an amount from about 0.1 to 1 part total additive per 100 parts of the sympathomimetic amine as a free base, hydrochloride salt, or sulfate salt, wherein the odorant or the mixture of two or more odorants selected from the group consisting of camphor, triethyl citrate, methyl anthranil, isoamyl acetate, geranyl acetate, linalool, alpha ionone, ortho-nitroacetophenone, and ortho-aminoacetophenone.
2. The pharmaceutical composition of claim 1 wherein said additive is co-distillable with the free base of said sympathomimetic amine.
3. The pharmaceutical composition of claim 1 wherein said additive is co-steam distillable with said sympathomimetic amine as a free base, hydrochloride salt, or sulfate salt.
4. The pharmaceutical composition of claim 3 wherein said additive is co-steam distillable with the free base of said sympathomimetic amine.
5. The pharmaceutical composition of claim 3 wherein said additive is co-steam distillable with the free base of said sympathomimetic amine as a free base, hydrochloride salt, or sulfate salt and is substantially unextractable from said sympathomimetic amine as a free base, hydrochloride salt, or sulfate salt.
6. The pharmaceutical composition of claim 3 wherein said additive is substantially unextractable by methanol extraction, n-hexane extraction, or acid/base extraction.
7. The pharmaceutical composition of claim 1 wherein the additive exhibits a vapor pressure at 100° C. which ranges from about 0.1 to about 10 times that of the sympathomimetic amine.
8. The pharmaceutical composition of claim 1 wherein the sympathomimetic amine is selected from the group consisting of ephedrine, phenylpropanolamine, and pseudoephedrine.
9. The pharmaceutical composition of claim 1 wherein said additive is an odorant.
10. The pharmaceutical composition of claim 9 wherein said odorant is co-distillable with said sympathomimetic amine as a free base, hydrochloride salt, or sulfate salt.
11. The pharmaceutical composition of claim 10 wherein said odorant is co-steam distillable with said sympathomimetic amine as a free base, hydrochloride salt, or sulfate salt.
12. The pharmaceutical composition of claim 1 wherein said additive is present in an amount sufficient to provide a product derived from distillation overhead wherein said product contains an odorant in an amount which is detectable by the mammalian sense of smell.
13. The pharmaceutical composition of claim 1 that comprises a further active ingredient selected from the group consisting of a fever reducer/pain reliever, an antihistamine, a cough suppressant/antitussive, an antihistamine/topical analgesic, and an expectorant.
14. A method of reducing the isolatability of a water soluble acid salt of a sympathomimetic amine from a pharmaceutical composition containing said acid salt of a sympathomimetic amine, which comprises including within said pharmaceutical composition an odorant or a mixture of two or more odorants which is co-distillable with the sympathomimetic amine as a free base, hydrochloride salt, or sulfate salt, in an amount from about 0.1 to 1 part total additive per 100 parts of said amine as a free base, hydrochloride salt, or sulfate salt.
15. The method of claim 14 wherein said additive is co-steam distillable with the sympathomimetic amine as a free base, hydrochloride salt, or sulfate salt.
16. The method of claim 14 wherein said additive is substantially incapable of separation from said sympathomimetic amine as a free base, hydrochloride salt, or sulfate salt by a method or methods selected from the group consisting of solvent extraction, precipitation, simple distillation, and crystallization.
17. The pharmaceutical composition of claim 1 wherein said additive is a mixture of two or more odorants.